Positive locking mechanical coupling arrangement

ABSTRACT

A positive locking arrangement is disclosed for coupling with the wall portion of the first component carrying the locking means sandwiched in between. A rotatably actuated locking ring member having a spaced clearance hole and connected slot arrangement together with ramp bearing and spring force exerting means is adapted to receive and retain in the hole portion stud members positioned in a second component. The components are interlocked by a rotational movement of the ring member. Rotation in a reverse direction unlocks the components. In an illustrative embodiment a magnetron energy generator having an external magnetic field producing means and incorporating the mechanical arrangement is supported by appendages in the launching waveguide section of a high frequency heating apparatus.

United States Patent 1 Foerstner et al.

[ 1 May 15, 1973 [54] POSITIVE LOCKING MECHANICAL COUPLING ARRANGEMENT [75] Inventors: Richard A. Foerstner, Iowa City,

Iowa; James R. Mims, Acton, Mass.

[73] Assignee: Amana Refrigeration, Inc., Amana,

Iowa

[22] Filed: June 11, 1971 [21] App]. No.: 152,309

[56] References Cited UNITED STATES PATENTS 3,662,140 Jones et al 2l9/l0.55

Biesecker ..24/221 L Primary ExaminerJ. V. Truhe Assistant ExaminerHugh D. .Iaeger Attorney-Harold A. Murphy, et al.

[57] ABSTRACT A positive locking arrangement is disclosed for coupling with the wall portion of the first component carrying the locking means sandwiched in between. A rotatably actuated locking ring member having a spaced clearance hole and connected slot arrangement together with ramp bearing and spring force exerting means is adapted to receive and retain in the hole portion stud members positioned in a second component. The components are interlocked by a rotational movement of the ring member. Rotation in a reverse direction unlocks the components. In an illustrative embodiment a magnetron energy generator having an external magnetic field producing means and incorporating the mechanical arrangement is supported by appendages in the launching waveguide section of a high frequency heating apparatus.

6 Claims, 9 Drawing Figures PAIENTED MAY] 5 I975 SHEET 2 OF 3 60a Ill F/G. 5 V

PATENTED HAY 1 51973 SHEET 3 [IF 3 20 nag/H 74 MAGNETRON ENERGY GENERATOR ASSEMBLY HIGH VOLTAGE SUPPLY BACKGROUND OF THE INVENTION The invention relates to mechanical coupling arrangements requiring interlocking of components and microwave heating apparatus.

Magnetron energy generators having external permanent magnet or electromagnetic field producing means are utilized in microwave heating apparatus in the manner well known in the art. Such energy generators have an output member positioned within a waveguide launching section coupling the energy to an enclosure. Conventionally, such members comprise a dome of a dielectric material housing a probe antenna inserted within an opening in a wall of the waveguide launching means. The mounting of the energy generator or removal for replacement can result in breakage of the dielectric member with resultant loss of the vacuum condition and failure of the device.

The generators are also cumbersome and heavy due to the magnets. Prior art mechanical arrangements for coupling such generators in the heating apparatus utilized conventional fastening members such as bolts, slotted or Allen head screws and the like along with brackets, flanges or springs. The associated electrical circuitry and high voltage power supply is installed adjacent to the energy generator which restricts the space available if the apparatus size is to be held within reasonable limits. The accessibility factor as well as the need for careful positioning of the energy generator then has resulted in high labor cost for both installation and replacement of these heavy and bulky components. A need arises, therefore, for a simple and inexpensive positive locking mechanical arrangement.

SUMMARY OF THE INVENTION connected slots. The hole dimensions are selected to receive the shank of stud members secured and appended to a second mechanical component to be coupled to the first component bearing the locking arrangement. A groove in the shank of the stud members is dimensioned to be movable within the slot portion. After insertion of the stud members within the holes a rotational movement in an arc of, for example, 30 will position the groove. of the stud/members within the slots.

. The rotatable member is provided with ramp bearing portions adjacent the slot and spring fingers at points intermediate the hole and slot arrangements to provide force exerting means on opposite surfaces to further secure and positively lock the coupled components. The problems of accessibility are readily solved since the rotatable member may be actuated from a position removed from the coupling interface. In an alternative embodiment, a stop is provided by an extension in the outer peripheral wall of the rotatable member to contact suitable structure. Rotation to the stop position indicates when the stud members are aligned within the holes to thereby assist in the removal or installation operation.

In applications involving magnetron energy generators with magnetic field producing means the structure housing the rotatable member is fabricated of asuitable ferrous'magnetic material, such as steel, as well as the rotatably actuated member. The new coupling arrangement provides assistance in the installation and correct positioning of the magnetron energy generator with the output member disposed within the waveguide launching section. Installation is also achieved in a very short time since rather difiicult manual fastening operations have been eliminated in the coupling of the compo nents.

BRIEF DESCRIPTION OF THE DRAWINGS Details of the invention will be readily understood after consideration of the following description and reference to the accompanying drawings, wherein:

FIG. 1 is an isometric view of the illustrative embodiment of the invention;

FIG. 2 is a side elevational view of a magnetron energy generator embodiment incorporating the inventron;

FIG. 3 is an enlarged fragmentary cross-sectional view taken along the line 33 in FIG. 2;

FIG. 4 is a plan view of a rotatably actuated locking member embodying the invention; I

FIG. 5 is a fragmentary cross-sectional view along the line 5-5 in FIG. 4;

FIG. 6 is a fragmentary cross-sectional view taken along the line 6-6 in FIG. 4;

FIG. 7 is a plan view of an alternative rotatably actuated locking member embodying the invention;

FIG. 8 is an isometric view of a microwave heating apparatus embodying the invention; and

FIG. 9 is a vertical cross-sectional view of the microwave heating apparatus shown in FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT The embodiment of the invention, particularly for use in combination with a magnetron energy generator, is illustrated in FIGS. 1-3 inclusive. The magnetron assembly 10 comprises a conductive envelope 12 within which an anode having circumferentially disposed plural resonant cavities is housed as well as an indirectly heated central cathode. The magnetic field producing means 14 include permanent magnet members surrounded by asubstantially U-shaped support and houstaken ing member 16 which forms the magnetic field return path.

The electromagnetic energy is coupled from generator 10 by means of an output radiating antenna probe 18 housed within dielectric dome member 20. The generator is energized by means of high voltage leads 22 and 24 connected to the magnetron cathode through an RF shielded bypass capacitor means housed within box member 26. This latter component is secured to plate member 28 which is secured by welding or solder ing to complete the housing member 16. Cooling fins 30 surround the conductive envelope to provide for the direction of circulating air for rapid removal of the heat generated by the high frequency oscillations.

Magnetic return path member 16 comprises top wall 32 and parallel sidewalls 34 and 36 to define a substantially U-shape configuration. Opening 38 provides for the insertion of dielectric dome member 20. A rotatably actuated locking ring member 40 surrounds the opening 38 and is supported by equidistantly spaced overlapping lances 42 provided in top wall 32. Member 40 is provided with circumferentially disposed clearance holes 44 and connected slots 46. Holes 44 are dimensioned to accommodate stud members 48 appended to a component to be coupled to the ring member-bearing component 16. Each stud member 48 has a shank portion 50 and groove 52 interrnediately disposed therein as illustrated in FIG. 3. Mating holes 39 are spaced in top wall 32 to receive the stud members 48.

Rotation of member 40 by means of manual actuation of control handle 54 in the direction indicated by arrow 56 provides for positioning the stud grooves 52 within slots 46 until the end walls 58 are contacted. In the illustrative embodiment the dimension of holes 44 to receive stud member 48 is approximately twice the width of slots 46 which receive grooves 52 for positive locking. Handle 54 is moved through an arc of less than 45 in embodiments having four equidistant stud members 48. A 30 arc will suffice in most applications to achieve the desired positioning.

Attention is now directed to FIGS. 4-6 illustrative of another feature of the invention. To assure positive locking of the ring member 40 upon rotation within stud grooves 52 means for exertion of oppositely extending forces are positioned in planar surfaces 60 and 61. Spring finger members 62 are disposed intermediately to the hole 44 and slot 46 arrangements. Members 62 extend from surface 61 and thereby contact surfaces overlying locking ring member 40 in a mounting position with surface 61 bearing against wall 32. Referring again to FIG. 3, stud members 48 are supported by a metallic wall 64 of, for example, waveguide launching section 66 of a microwave heating apparatus 68. The spring fingers 62 would be compressed against wall 32 of the magnetic field return path member 16. Wall 32 in the illustrative mounting arrangement also bears against the cover member 70 positioning RF gasket 72 within opening 38 to prevent escape of electromagnetic energy. Another opening 74 in waveguide wall 64 is aligned with opening 38 in return path member 16 for introduction of dome member of the energy generator.

With the disclosed mounting arrangement wall member 32 is sandwiched between locking ring member 40 and another mechanical component, namely wall 64. To further assist in maintaining the position of the interlocked components a ramp bearing portion 76 is provided by an identation in surface 60 in the vicinity of narrow slots 46 and the adjacent wall surfaces 60a. As seen in FIG. 3, the ramp 76 exerts a holding pressure within grooves 52. Combined with spring fingers 62 extending in the opposite direction positive locking forces are applied. It is desirable that ramp portions 76 and members 62 be fabricated of a resilient material so as to be capable of being flattened without taking a permanent set.

In FIG. 7 an alternative locking ring member 40 is illustrated having handle portion 54 of a squared end configuration. Finger members 78 are notched in the peripheral wall adjacent centrally disposed opening 80. A further modification is provided by means of an extension defining a stop portion 82 adjacent one of slots 44. A flattened wall 84 in the portion of the peripheral edge will also assist in movement of the locking ring member within the holding means, such as lances 42. In FIG. 1 such a stop arrangement is illustrated to assist the user in orienting stud members 48 relative to holes 44 when it is difficult to align components in inaccessible areas. With the stop 82 preventing further rotation the component to be coupled can be inserted and the handle 54 rotated 30 or the required distance to lock the components. Similarly, for easy removal the handle may be rotated in the opposite direction until the stop is engaged which will align the stud members 48 within holes 44 and permit the component to be separated.

Referring to FIGS. 8 and 9, an exemplary microwave heating apparatus 68 incorporating the embodiment of the invention is illustrated. Such devices commonly employ a magnetron generator which radiates frequencies of 2,450 megahertz corresponding to a wavelength of approximately 5 inches in space. For the purposes of the present description, the term microwaves" refers to electromagnetic radiation in that portion of the spectrum having wavelengths of from 30 centimeters to l millimeter. Rectangular parallelepiped conductive walls 86 define heating enclosure 88 having an access opening provided with a door 90. Handle 92 provides for manual opening and closing of the door. Control panel 94 is disposed adjacent to the access opening with the electromagnetic energy generation means and accompanying circuitry disposed behind.

The energy generator, illustratively the magnetron assembly 10 previously described, is coupled to a high voltage supply and electrical controls indicated generally by block 96. The electromagnetic energy is fed from the magnetron 10 by means of a radiating probe 18 in the dielectric dome member 20 to the launching waveguide section 66 adapted to couple the desired microwave into enclosure 88. Waveguide 66 is shortcircuited at one end by wall 98 and is open at the inner end 100. The energy may be distributed within the enclosure by any means known in the art such as, for example, a stirrer 102 having vanes 104 actuated by motor means 106. The articles to be heated are supported on dielectric plate 108 within enclosure 88.

The invention makes possible an efficient and simple method-of coupling the magnetron energy generator within the waveguide launching section by a manual rotation of the handle of the-locking ring member 40 with stud members 48 positively locked in slots 46. Installation and replacement with the required positioning of the energy output member is thereby facilitated with a minimum of mechanical steps and breakage is virtually eliminated.

Modifications and variations in the disclosed structure will become apparent to those skilled in the art. It is intended, therefore, that the foregoing description of the illustrative embodiment be considered in its broadest aspects and not in a limiting sense.

We claim:

1. A microwave energy generator'comprising:

a conductive envelope having an output antenna member extending axially from one side and external magnetic field producing means supported within a metallic magnetic field return path member;

said metallic member carrying on a wall adjacent to said antenna member a rotatably actuated locking ring member;

said ring member having a clearance hole and slot arrangement;

said hole and slot dimensions being adapted to receive and retain metallic stud members appended to a second wall to be interconnected with said generator upon rotation of said ring member.

2. A generator according to claim 1 wherein said locking ring member is supported by means of overlapping lance portions in said wall of said magnetic field return path member.

3. A generator according to claim 1 wherein an outwardly disposed stop is provided along a portion of the outer peripheral edge of said ring member.

4. A generator according to claim 1 wherein said ring member comprises a ramp portion adjacent to each hole and slot arrangement and spring finger members disposed intermediate to said ramp portions.

5. High frequency heating apparatus comprising:

an enclosure;

means for launching microwave energy within said enclosure comprising a section of rectangular waveguide;

a microwave energy generator having an output antenna member extending axially from one end and a magnetic field return path member; and

means for coupling said generator to a wall of said waveguide comprising a rotatably actuated locking ring member mounted on a wall of said magnetic field return path member adjacent to said antenna member;

one of said waveguide walls having plurality of spaced metallic stud members;

said ring member having a plurality of spaced clearance hole and slot arrangements adapted to receive and retain said metallic stud members upon rotation to interlock the contacted components.

6. The apparatus according to claim 5 wherein said ring member comprises a ramp portion adjacent to each hole and slot arrangement extending in one direc tion from the planar surface of said ring member and intermediately disposed spring finger members extending in the opposite direction from said surface. 

1. A microwave energy generator comprising: a conductive envelope having an output antenna member extending axially from one side and external magnetic field producing means supported within a metallic magnetic field return path member; said metallic member carrying on a wall adjacent to said antenna member a rotatably actuated locking ring member; said ring member having a clearance hole and slot arrangement; said hole and slot dimensions being adapted to receive and retain metallic stud members appended to a second wall to be interconnected with said generator upon rotation of said ring member.
 2. A generator according to claim 1 wherein said locking ring member is supported by means of overlapping lance portions in said wall of said magnetic field return path member.
 3. A generator according to claim 1 wherein an outwardly disposed stop is provided along a portion of the outer peripheral edge of said ring member.
 4. A generator according to claim 1 wherein said ring member comprises a ramp portion adjacent to each hole and slot arrangement and spring finger members disposed intermediate to said ramp portions.
 5. High frequency heating apparatus comprising: an enclosure; means for launching microwave energy within said enclosure comprising a section of rectangular waveguide; a microwave energy generator having an output antenna member extending axially from one end and a magnetic field return path member; and means for coupling said generator to a wall of said waveguide comprising a rotatably actuated locking ring member mounted on a wall of said magnetic field return path member adjacent to said antenna member; one of said waveguide walls having plurality of spaced metallic stud members; said ring member having a plurality of spaced clearance hole and slot arrangements adapted to receive and retain said metallic stud members upon rotation to interlock the contacted components.
 6. The apparatus according to claim 5 wherein said ring member comprises a ramp portion adjacent to each hole and slot arrangement extending in one direction from the planar surface Of said ring member and intermediately disposed spring finger members extending in the opposite direction from said surface. 